I was doing a math problem this morning and realized that the solution lied in the fact that if a function of A -> A is one to one then it is onto. It is so obvious that I have been taking it for granted for so long time.(adsbygoogle = window.adsbygoogle || []).push({});

But now when I think of it deeply, I find it very interesting and relating to some foundational questions like set theory and relation.

Hope you can join with me working on this.

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# How to prove a one to one function A -> A is also a onto function?

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